CMV: It's unprofessional if a teacher allows a student to walk up and hug them.

This post was inspired by a similar discussion I've had in r/teachers. I've had multiple students walk up to me and give me a hug unprompted. I try to be as nice and caring as a person as possible, but I don't think it's appropriate for a student to give me a hug. I like to draw a line between being a nice person and unprofessionalism. <br><br>So now I'm curious, if anyone on this website holds a different view. <br><br>Edit: I've been teaching 7th-8th grade middle school, so ages 12-14. The school is in the USA.